Intelligent Screensavers

How many times have you been to a presentation where the presenter’s screensaver or screen blanker kicks in 5 minutes in to the presentation, and then every so often thereafter, causing them to have to stop in mid-flow and swipe their finger over their trackpad to restore their slide to view?

It would be great if the GNOME screensaver (or that of other free software platforms) were able to detect that the screensaver had been automatically dismissed immediately after being invoked (say within 10 seconds), and decide to disable the screensaver entirely for the next hour or so. Possible loss: some energy. Possible gain: a much more pleasant presentation. Good trade-off? If this made too many false positives, then perhaps it could switch it off only after 2 consecutive sub-10-second dismissals.

21 thoughts on “Intelligent Screensavers

  1. Instead of random guessing, wouldn’t a better solution be for presentation apps to send some sort of notification to the screensaver when presenting started and ended, so that the screensaver would know for certain not to come on during that time?

  2. I think powerpoint disables the screensaver by default; I can’t remember the last time I saw a screensaver come on during a presentation. A scheduled virus scan that turns the computer to molasses, on the other hand…

  3. Smokey: sure, and many apps do, but some people present with e.g. Firefox, which probably shouldn’t send such notifications. And also, you aren’t always showing a presentation app or video app.

    Erik: You are right on both counts :-)

  4. Add the Inhibit Applet to your panel and activate it when you give a presentation. Not quite as good as having the screensaver figure it out except that you won’t have even one screensaver activation during the presentation. Just don’t forget to turn it off ;)

  5. “It would be great if the GNOME screensaver (or that of other free software platforms) were able to detect that the screensaver had been automatically dismissed immediately after being invoked (say within 10 seconds), and decide to disable the screensaver entirely for the next hour or so.”

    None of the proposed solutions takes into account something like an automatic slide show. From the user point of view, a simpler method is just to take into account screen activity as well as keyboard and mouse. The current system considers only keyboard and mouse activity as evidence of user interest. If the screen keeps changing, just assume it’s needed.

  6. Wouldn’t it make sense for GNOME to disable the screensaver if it detects *any* fullscreen app running? Or at the very least, set it to a really long timeout…

  7. I like VanillaMozilla’s suggestion. It would have to be tweaked to care about the *amount* of change, so that something like dclock with seconds or a terminal window running xmms2 status or tail -f wouldn’t prevent blanking. But I think most presentations and slideshows have a lot more change than that. (Hmmm… maybe the amount of change required should be an adjustable slider…)

  8. Yippe. Caffine looks promising for keeping the screensaver at bay when you want the capability of using something like Firefox for longer than your screensaer init time and you don’t want to have to fiddle with the settings.

    For gnome, I found this

    http://library.gnome.org/users/gnome-power-manager/stable/faq.html.en

    Go to section
    8.11.  How do I make my application stop the computer auto-suspending?
    8.12.  Are GNOME Power Manager and GNOME Screensaver inhibit methods the same?

    In windows, it can be as simple as eating this message :

    When the computer has been idle for a time, the system sends a WM_SYSCOMMAND message to the current foreground window with argument SC_SCREENSAVE. If the active window is not a windows application, or if it gobbles up the message, then nothing further happens.

  9. This is something I have been looking for. On Windows XP
    caffeine -exitafter:45 is doing just what I want. A wife friendly way to click a shortcut and temporarily inhibit the screensaver while we do out workouts while using Firefox.

    For gnome, look here on the gnome api site

    http://library.gnome.org/users/gnome-power-manager/stable/faq.html.en

    8.11. How do I make my application stop the computer auto-suspending?

    8.12. Are GNOME Power Manager and GNOME Screensaver inhibit methods the same?

    BTW,in your own windows program its as simple as:
    When the computer has been idle for a time, the system sends a WM_SYSCOMMAND message to the current foreground window with argument SC_SCREENSAVE. If in your message handling procedure you do not pass it on to DefWindowProc, no screen saver is activated

  10. I use a Makefile to compile my LaTeX-beamer presentations. The “present:” target of that Makefile just does “xscreensaver-command -disable” before calling xpdf and then “xscreensaver-command -enable” afterwards (ie: after xpdf exits).

    I don’t see a reason to introduce “intelligence” into software when it can be simply implemented by human cleverness.

  11. Why not just run “gnome-screensaver-command -i” before running your presentation? The command will stop the screensaver from activating until you ^C it. I use it when playing Armagetron Advanced, because the screensaver likes to come on in the middle of the game for some reason.

  12. “A scheduled virus scan that turns the computer to molasses, on the other hand…”

    It seems that this sort of thing is not a new phenomenon. I once saw an amusing video clip of an “out-take” from a televised weather forecast from the relatively early days of using computerised graphics for forecasts rather than have the forecaster physically stick weather symbols onto a map. Just before the live broadcast, they were meant to lock computing resources from the Met Office’s system so that these would be reserved for use by the presentation rather than for other tasks. On one occasion they forgot to do this, and during the live broadcast the system went completely out of control and started just displaying random wind arrows all over the map, while the red-faced forecaster just looked on helplessly and was completely unable to deliver a meaningful forecast.

  13. If your screensaver kicks in during a presentation because you spent 5+ minutes on a single static slide, then your presentation is not well designed.

  14. Michael: I disagree. I’ve listened to great sermons which are half an hour long and have four or five slides. Presentations are a support for what you are saying; the current 150+-slide slide-per-sentence style is only one way of presenting, and some would argue not the best way.